OSHA finally may update ionizing radiation rule

Increase in X-ray uses prompts review

More than 30 years after first creating a standard on ionizing radiation, the U.S. Occupational Safety and Health Administration (OSHA) wants to determine if the rule needs an update. The review was prompted by the growth in potential exposures to ionizing radiation with new medical uses and increased prevalence of security screening devices, OSHA said.

“We’ve detected a very large increase in that type of activity — not only in public buildings but also in private buildings,” an OSHA official said. “We believe the increased use of X-ray devices is certainly one reason why we want to look at our standards — whether to update them and how to update them.”

Regulatory jurisdiction related to radiation exposure is split among several agencies. The Nuclear Regulatory Commission (NRC) regulates uses of radiation that are byproducts of nuclear power, including such radiopharmaceuticals as iodine-131 and technetium-99m. State radiation protection programs have licensing and inspection authority regarding X-rays, including CT scanners and radioactive material that is produced by accelerators. The Food and Drug Administration has jurisdiction over the production of many radiopharmaceuticals, including those used in positron-emission tomography (PET) and the radiation exposure of research subjects in clinical trials.

In addition, OSHA standards cover worker exposures from radiation sources such as x-ray equipment, accelerators, accelerator-produced materials, electron microscopes, and naturally occurring radioactive materials that are used in the workplace.

Thirty-three states conduct their own radiation protection program under an agreement with the NRC. Another 17 have direct inspections and oversight from the NRC.

OSHA posed more than 50 questions about radiation use, including who’s exposed, how much exposure employees have, and what employers are doing to minimize exposure.

“It’s a complicated area. It deserves a lot of questions,” the OSHA official commented. “The point of our RFI [request for information] is to get hospitals and everybody else who has employees who are potentially exposed to X-rays to tell us what they’re doing.”

Radiation use in medicine has greatly expanded, but exposures remain low, says Robert Reiman, MD, MSPH, assistant clinical professor of radiology at Duke University Medical Center in Durham, NC. Reiman is a nuclear medicine physician, and he oversees clinical operations in radiation protection at the hospital.

“For most health care workers, the exposures are very, very low. They don’t even approach a tenth of the current occupational limit,” he says.

In fact, that should be the goal of employee protection programs, Reiman continues.

“There’s a concept in radiation protection [called] ALARA — as low as reasonably achievable. What you strive to do is make sure everyone’s dose is below that 10% of occupational exposure. We badge a lot of people who are below that 10% level to make sure we’re in compliance with the ALARA program,” he says.

Some employees, such as those working with radiopharmaceuticals, should wear a ring badge as well as a body badge to monitor exposure to both the body and hands, Reiman advises. The NRC sets an occupational exposure limit of 5 rem whole body exposure in a year. The OSHA rule limits exposure to 1.25 rem per quarter.

“They’re set at a level that we believe, even with chronic long-term exposure over a working lifetime — [that is] 20 to 30 years — the person has a good chance of not having any radiation-induced effects,” he says.

Pregnant employees have a limit of 500 mrem during the gestation period, and they wear a waist-level monitor to check potential fetal exposure. At Duke, pregnant employees may have some accommodations and stop doing some activities, such as handling radioactive iodine, Reiman says.

[Editor’s note: A copy of OSHA’s Federal Register notice seeking comments on the ionizing radiation rule is available at www.osha.gov/SLTC/radiationionizing/index.html. The deadline for comments is Aug. 1. Comments may be faxed to OSHA’s Docket Office at (202) 693-1648 or sent electronically to http://ecomments.osha.gov. A copy of OSHA’s standard on ionizing radiation is available at www.osha.gov/SLTC/radiationionizing/standards.html.]